This invention pertains to methods and apparatus for storing data. More specifically, the invention pertains to methods and apparatus for storing data which methods and apparatus employ hard disk data storage media which are enclosed within a cartridge shell.
Many various types of prior art data storage apparatus and methods are known. Of the known data storage systems, two of the more widely used types are those which comprise tape drives and those which employ hard disk drives. As the respective names imply, tape drives and hard disk drives each employ specific types of media on which to store data. That is, tape drives employ reels of magnetic tape strips as data storage media, while hard disk drives employ one or more stacked hard disk xe2x80x9cplattersxe2x80x9d as data storage media.
Typically, the magnetic tape type of media is supported on one or more reels which are enclosed in a cartridge shell, or casing. The tape, together with the cartridge shell, is referred to as a xe2x80x9ctape cartridge.xe2x80x9d Such tape cartridges are configured to be selectively placed into a slot, or opening, of a tape drive, wherein the tape is extracted from the cartridge so that data can be read from, and/or written to, the tape. When the reading, and/or writing, of the tape is completed, the tape is wound back into the cartridge, and the tape cartridge is removed from the slot of the tape drive and placed on a storage rack or the like. The cartridge configuration of the tape facilitates ease of handling a great number of tapes, wherein each tape cartridge can be quickly exchanged between a storage position and a tape drive for read/write operations.
Tape cartridges typically adhere to one of a plurality of accepted cartridge form factors. By xe2x80x9ccartridge form factorxe2x80x9d I mean a given set of standardized physical configurational and dimensional criteria which apply to the design of cartridges. Various specific data storage cartridge form factors have been developed, and include cartridge form factors known by the designations of: DAT (Digital Audio Tape); DDS (Digital Data Storage); DLT (Digital Linear Tape); and LTO (Linear Tape Open) The adherence of tape cartridges to a given known standard cartridge form factor allows for wide spread interchangeability of tape cartridges which adhere to a common form factor.
Often, a plurality of tape cartridges are employed in conjunction with an automated library system or the like. Automated library systems typically comprise storage racks or supports, at least one robotic cartridge handling device, and at least one tape drive. The storage racks are configured to support the plurality of tape cartridges. The robotic cartridge handling device is configured to selectively move given tape cartridges from the storage rack to the tape drive, and to insert the tape cartridge into the slot of the tape drive. While the tape cartridge is in the slot of the tape drive, read/write operations can be performed on the tape. The robotic cartridge handling device is also configured to remove the respective tape cartridges from the tape drive after the read/write operations have been performed on the tape cartridge, and to replace the tape cartridges onto the storage rack.
Thus, a typical automated library system is configured to move tape cartridges between respective stored positions on a storage rack and a tape drive, as required. Generally, a controller or the like is used to control the operation of the automated library system. For example, a controller, when connected in signal communication with the robotic handling device, can be configured to direct the robotic handling device to move a specific, given tape cartridge from its stored position on the storage rack to a tape drive in response to a requirement to retrieve given data which is stored on the given tape cartridge. As is evident, tape cartridges, when used in conjunction with an automatic library system, for example, are relatively well-suited for long-term storage and archiving of large amounts of data. However, one disadvantage of magnetic tape is that data reading/writing operations are relatively slow compared to magnetic hard disks, for example. Moreover, accessing random portions of data from magnetic tape can be significantly slow compared to magnetic hard disks.
Hard disks are generally known to provide exceptionally rapid data storage and retrieval, as well as high levels of storage capacity. Hard disks are typically employed in xe2x80x9cdisk arrays.xe2x80x9d A typical disk array comprises a frame or rack that is configured to support a plurality of modules or the like which each contain one or more hard disks along with a disk drive. The modules which contain the hard disks and disk drive are generally configured to be semi-permanently supported on the frame or rack. That is, the modules are generally configured to remain supported in place on the frame or rack and communicatively linked with at least one other device, except for repair and/or replacement of a malfunctioning module in which case the malfunctioning module is communicatively disconnected from the other respective devices and removed from the array. In other words, prior art data storage methods and apparatus which employ a plurality of hard disks are typically limited in regard to the functional use of each hard disk to situations in which all of the hard disks are communicatively linked together so as to be immediately available, on demand, for read/write operations. As a result, the prior art use hard disks for data storage necessitates relatively large and cumbersome disk arrays which comprise a great number of modules.
What are needed then, are data storage methods and apparatus which achieve the benefits to be derived from similar prior art devices, but which avoid the shortcomings and detriments individually associated therewith.
The invention includes methods and apparatus for the storage of data wherein a disk cartridge is employed. The disk cartridge is a primary focus of the instant invention, wherein the disk cartridge comprises a hard disk storage medium which is operably supported within a cartridge shell. The disk cartridge can be quickly retrieved from a communicatively isolated storage condition and temporarily communicatively linked to a device such as a host computer, whereupon data can be transmitted between the host and the disk cartridge, such as in read/write operations. The term xe2x80x9ccommunicatively isolatedxe2x80x9d as used herein means that the disk cartridge is not linked by any communication means to any other device. When the disk cartridge is not required for read/write operations, the disk cartridge can be communicatively unlinked, or disconnected, from the host computer, for example, and restored to its communicatively isolated condition, wherein the disk cartridge is not communicatively linked to any device.
In accordance with one embodiment of the present invention, an apparatus for storing data includes a disk cartridge and a docking device which is configured to temporarily accept the disk cartridge in communicative linkage therewith. That is, the docking device is configured to temporarily support the disk cartridge during which time the docking device and the disk cartridge are in signal communication with one another so that data can be transmitted there between. The disk cartridge comprises a cartridge shell and a hard disk memory medium operably supported within the cartridge shell. The disk cartridge can be moved to the docking device either manually or by way of an automated cartridge handling system or the like. The cartridge shell can adhere to a known cartridge form factor so that existing cartridge handling systems can be employed.
In accordance with another embodiment of the present invention, a data storage apparatus includes a disk cartridge which has a cartridge shell, a hard disk supported within the cartridge shell, and a cartridge interface mounted on the cartridge shell. The apparatus also includes a docking device which defines a receptacle configured to receive the cartridge shell. The docking device further includes a docking device interface which is mounted on the docking device and which is configured to interact with the cartridge interface, thereby communicatively linking the disk cartridge and the docking device. The docking device interface can be, for example, a connector (such as a pin connector), or a wireless connection, such as by infrared data transmission or the like. The apparatus can further include a tape cartridge and a tape drive which is configured to accept the tape cartridge for performance of read/write operations thereto. The tape drive can be integrated into the docking device. Furthermore, the tape cartridge and disk cartridge can adhere to a common cartridge form factor. This can allow for both the tape cartridge and the disk cartridge to be employed in conjunction with a single docking device which is configured to communicatively link with both the tape and disk cartridges.
In accordance with another embodiment of the present invention, a data storage method includes providing a hard disk memory medium, and providing a host device. The method also includes storing the hard disk memory medium in a communicatively isolated condition and communicatively linking the hard disk storage medium to the host device. This can allow for data to be written to the hard disk memory medium from the host device. After data is written to the hard disk memory medium from the host device, the hard disk is restored to a communicatively isolated condition. After a period of time has elapsed, the hard disk memory medium can be communicatively re-linked to the host device. That is, the hard disk can be linked again in signal communication with the host device. Data can thus be read from the hard disk memory medium to the host device. That is, data can be read from the hard disk and transmitted to the host device. The hard disk memory medium can be at least a portion of a disk cartridge, wherein the hard disk is operably supported within a cartridge shell. The communicative linkage of the hard disk with the host device can be accomplished by way of docking device into which the disk cartridge can be placed. The disk cartridge can be placed into the docking device by an automatic cartridge handling device.